The present invention relates to a window closure system for swingably attaching and locking a casement window to a window frame, and more particularly a corrosion resistant window closure system for use in marine, coastal and other high humidity environments where increased susceptibility to corrosion occurs.
Various window hardware systems have been proposed to swingably attach and secure casement windows to a window frame. For example, residential casement windows are typically swingably attached to the window frame by a hinge assembly which is operable by means of a hand crank, and which further includes a hinge arm coupled along the window frame and an elongated L or U-shaped track coupled along a horizontal lower edge of the window sash. The hinge arm is pivotally movable with the window sash, with its other end slidable along the track. A swivel arm is pivotally joined at each of its ends to the track and a mid point of the hinge arm to assist in the outward and inward movement of the hinge arm.
The window may be locked or unlocked by the reciprocal movement of an elongated tie bar which is slidably mounted along one side of the window frame. The tie bar carries one or more bosses or projections which are moved into or out of engagement with ramped caming members mounted on an adjacent portion of the window sash, as for example is disclosed in the applicant""s U.S. Pat. No. 6,109,668, issued Aug. 29, 2000.
Conventional hardware used in the attachment of casement windows in window frames suffers the disadvantage in that it is susceptible to premature corrosion, particularly when used in marine, coastal or other high humidity environments. In particular, conventional window hardware swivel arms, hinge arms and tie bars are typically formed from 3 to 4 mm thick solid steel bars. To delay the effects of corrosion and prolong the window hardware life span, it is known to provide corrosive-resistant zinc platings on the swing and hinge arms, and the tie bar assemblies. It has been found, however, that metal-on-metal contact which occurs with window hardware operation tends to scratch away portions of the protective coating and expose the unprotected underlying steel. This problem is particularly acute at the pivot points and where the tie bars move into contact with the ramped caming members. As a result, the areas of metal-on-metal contact are susceptible to premature corrosion, especially when the hardware is used in such corrosive environments. In addition to initially creating an unsightly appearance, corrosion will ultimately weaken the hinge and locking mechanisms, leading to corrosion embrittlement and fatigue, and ultimately the failure of the window hardware.
While the applicant has considered forming the window hinge arms, swivel arms, and tie bars from solid 2 to 3 mm thick stainless steel stock, so as to prevent corrosion, the increased difficulties in machining and working with such solid stainless steel bars, and the higher costs associated therewith have heretofore made such modifications cost prohibitive.
To at least partially overcome the disadvantages of prior art window hardware systems, the present invention provides a window closure assembly used to secure a casement window to a window frame, and which includes an elongated rigid closure member useful as a swivel arm, hinge arm and/or tie bar, which is formed by folding a sheet of stainless steel or a stainless steel alloy into two, three or more substantially overlapping layers.
Another object of the invention is to provide hardware used to swingably secure a window sash to a window frame which is highly resistant to corrosive forces so as to prolong its operational life in marine, coastal and other high humidity environments.
Another object of the invention is to provide a window closure member which is suitable for use as a hinge arm, a swivel arm, a tie bar or other window hardware components and which is characterized by multiple juxtaposed stainless steel or other corrosion resistant sheet layers, which are joined together as an elongated rigid multi-layer laminate bar.
Another object of the invention is to provide an elongated bar for use as a window hinge swivel arm, hinge arm or a tie bar which is characterized by at least two juxtaposed metal layers, and which further includes at least one keeper member engaging at least a part of the upper and lowermost metal layers of the bar to assist in maintaining their juxtaposed orientation.
Another object of the invention is to provide an economical and easily fabricated corrosion resistant window closure system characterized by a swivel arm, hinge arm or tie bar for use in securing a window sash to a window frame, and which has an elongated portion formed entirely from multiple layers of stainless steel.
A further object of the invention is to provide a stainless steel or stainless steel alloy window closure member which is lightweight, economical to produce and which possesses substantially the same rigidity and strength as conventional window closure hardware made from solid steel bar stock.
The present invention provides a closure member to be used with a window closure system in securing a window sash to a window frame. The closure member is characterized by a corrosion resistant elongated rigid rectangular portion or body. Preferably, the elongated portion or body of the closure member is characterized by two, three or more stainless steel, stainless steel alloy or other corrosion resistant metal sheet layers provided in a juxtaposed and substantially overlapping orientation. Most preferably, the closure member is formed from folding one or more stainless steel sheets having a thickness selected at between about 0.25 and 2 mm, and more preferably, about 0.25 and 1 mm, and wherein an edge portion of the sheet is bent back against an adjacent portion to form a multi-layered laminate structure.
Although not essential, to provide the closure member with an aesthetically pleasing appearance while eliminating potentially dangerous sharp side edges, opposing longitudinal edge portions of the stainless sheet may be folded inwardly against a central portion of the sheet by bending along two longitudinal extending and parallel fold seams. Optionally, the stainless steel sheet may be bent along substantially folded seams which are spaced inwardly from the edges of the sheet, and most preferably fold seams spaced inwardly from the immediately adjacent edge by a distance which is approximately one-quarter of the total width of the sheet. The folded longitudinal edge portions of the sheet are bent so as to substantially directly overly the middle portion of the sheet bordered by the fold seams. As will be described, when so bent, the stainless steel sheet defines two generally planar juxtaposed metal layers, wherein one layer is a split layer which includes a longitudinally extending seam defined by the repositioned edges of the stainless steel sheet, and which extends longitudinally along a medial portion of the body.
The closure member may be used to secure a window sash to a window as part of a swivel arm, a hinge arm, and/or as part of a reciprocally movable tie bar used to selectively lock or unlock the window sash to the frame. Most preferably, the closure member is further characterized by one or more keeper members which engage the metal layers and prevent their movement from a juxtaposed orientation. Suitable keeper members may include without limitation, a caming or pivot boss which engages one or part of each of the outermost metal layers, to restrict their movement apart, or depending upon the intended application for the window closure member, the keeper member could alternately comprise one or more of a locking stud, a snap stud, a pivot stud, or other suitable pivot fastener. Although not essential, the keeper member is preferably positioned within a bore formed through the body so that once positioned, the keeper member engages the split metal layer on each side of any seam.
Accordingly, in one aspect the present invention resides in a hinge assembly for swingably attaching a window sash to a window frame, comprising,
a track assembly attachable to the window frame and including an elongated track,
an elongated swivel arm pivotally coupled at a first end portion to the track assembly, and
an elongated hinge arm extending from a first end to a second end, the first end being slidable along at least a portion of the track, a second other end portion of said swivel arm being pivotally coupled to the hinge arm at a pivot point intermediate said first and second ends,
the improvement wherein at least one of said swivel arm and said hinge arm comprises a closure member characterized by a rigid elongated rectangular body portion formed from a folded metal sheet and having at least two substantially juxtaposed metal layers, and wherein said metal layers are joined along at least one integral and longitudinally extending folded edge.
In another aspect, the present invention resides in a corrosion resistant window closure member for use as window hardware to secure a window sash to a window frame, said closure member comprising
an elongated rigid rectangular body portion having substantially parallel longitudinally extending edges, said body portion being formed from a stainless steel sheet and characterized by longitudinally extending folded edges, and two juxtaposed generally planer metal layers joined along each longitudinally extending folded edge.
In a further aspect, the present invention resides in a hinge assembly for swingably attaching a window sash to a window frame, comprising,
a track assembly attachable to the window frame and including an elongated track,
an elongated swivel arm pivotally coupled at a first end portion to the track assembly,
an elongated hinge arm extending from a first end to a second end, the first end being slidable along at least a portion of the track, a second other end portion of said swivel arm being pivotally coupled to the hinge arm at a pivot point intermediate said first and second ends, and
the improvement wherein at least one of said swivel arm and said hinge arm includes a closure member characterized by a elongated rectangular body portion comprising a plurality of juxtaposed metal layers being integrally and substantially continuously joined along longitudinally extending edges, and wherein said edges are formed from folding a single sheet of metal.